The embodiments herein disclosed relate generally to systems that move liquids from one vessel to at least one other vessel wherein the volumes and flow rates of the liquid being moved is controlled by a coordination of the simultaneous volumes and levels of liquid in each of the vessels at the same time.
The invention embodiments disclosed offer numerous improvements to many exiting multiple tank liquid storage and liquid transfer systems. One example of such multiple tank liquid handling systems is the common tabletop gravity fed water purification and filtration systems on the market currently. Such systems usually consist of two liquid holding tanks, one physically situated above the other, with a set of flow through water purification/filtration components that have a porous outer surface situated in the liquid flow path between the tanks. Unpurified water is poured into the upper tank, and the water flows by the force of gravity, out of the upper tank, into and through the water purification/filtration components, and then into the lower tank where it is stored as purified water.
Prior to embodiments disclosed here, existing systems have inherent in their design and construction the inconvenience that they need to be refilled manually. This is because the existing systems do not consist of means to automatically refill the tanks, nor are they comprised of means to detect when the purified water in the lower tank is below a desirable minimum level that indicates that refilling is needed. It is necessary for the user of the existing systems to observe when the lower tank is becoming empty which indicates that a manual refill is required, and then to refill the system manually by adding water to the upper tank. It is common with many of these existing systems for the user to need to refill them every day or so, based on how much of the purified water is drawn from the lower tank for drinking. The need for the user to refill the system manually on a repetitive basis is very inconvenient and an undesirable task. The manual refill procedure is performed by the user adding unpurified water to the upper tank. All of the liquid added to the upper tank will flow into and through a secondary process situated in the liquid flow path between the tanks, and then into the lower tank. In many cases the liquid flow rate through the secondary process will be very low and this low flow rate makes it very difficult for the user performing the manual refill procedure to judge correctly what volume of liquid, when added to the upper tank, will be too much, and thus will eventually cause the lower tank to overflow. These highly undesirable overflow events are frequent occurrences experienced by users of existing systems. The existing systems being manufactured and sold currently, are built lacking means to initiate and perform automatic refilling, and also lacking means to prevent tank overflows, and thus were the background and motivation for the embodiments of the invention disclosed herein.